JP2012084786A - Led package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED package in which an LED chip is surface mounted on a substrate and excellent heat radiation is conducted.SOLUTION: A substrate (1) mounting an LED chip (20) has plural conductive parts (11a)(11b) made of metal and an insulative part (12) made of inorganic material and electrically insulating the conductive parts (11a)(11b) from each other. The conductive parts (11a)(11b) and the insulative part (12) are integrally formed so as to be layered from a chip mount surface (M1) in a vertical direction, and the LED chip (20) is joined to the conductive part (11b) of the substrate (1).

Description

  The present invention relates to an LED package having excellent heat dissipation.

  A conventional LED package has an element mounted on a wiring board such as a lead frame, a ceramic substrate, a glass epoxy printed board, or a BT printed board, and electrodes fixed with wire bond, solder, high heat dissipation adhesive, or the like. It was general.

  In addition, with the recent increase in output of illumination and liquid crystal light sources, there is a tendency that the amount of heat generated by the LED chip or a package equipped with various LED chips increases. For this reason, in a board | substrate or a semiconductor component, favorable heat dissipation and the breaking strength with respect to a thermal stress are calculated | required.

  In general, the use of a ceramic substrate and the increase of the thickness of the lead frame are performed as means for improving the heat dissipation of the LED package.

  Japanese Patent Laid-Open No. 2004-228688 has a semiconductor element mounting portion on a ceramic insulating base, and a predetermined wiring board is provided in the vicinity of the outer peripheral edge of the connection pad in a wiring board in which an external electric circuit board is brazed to the lower surface of the insulating base via a connection pad. By providing a gap of the shape, the brazing part is prevented from being broken.

  The wiring board described in Patent Document 2 is such that a metal heat sink is embedded in an insulating material so as to penetrate the top and bottom of the board, and half etching is sequentially performed on the top and bottom surfaces of the metal plate to form recesses from both sides. And it manufactures by forming the insulating layer which penetrates a metal plate to an up-down direction by filling insulating resin in these recessed parts.

  The LED component described in Patent Document 3 is obtained by providing a ceramic substrate with a through hole, and brazing a heat sink with an LED chip mounted inside the hole.

  The light emitting element mounting substrate described in Patent Document 4 is obtained by printing an insulating layer on a green sheet formed on a thin plate with a slurry in which ceramic powder and a binder are mixed, printing a wiring pattern, and sintering. .

JP 2001-237529 A JP 2008-251671 A JP 2007-227728 A JP 2008-34513 A

  However, the techniques of Patent Documents 1 to 4 have the following problems due to the material and form of the substrate, respectively.

  The ceramic substrate has higher heat dissipation performance than the resin substrate, but is inferior to metal in terms of heat dissipation performance. Further, the cutting process and drilling process of the ceramic substrate requires a special processing technique to process the ceramic substrate so as not to break, so that the processing cost becomes high.

  In addition, the lead frame has a problem that it requires labor and cost, such as complicated processing. Moreover, since the insulating layer is made of resin, the difference in thermal expansion from the LED chip is large, and disconnection may occur due to thermal history due to repeated use.

  Further, in order to process a metal substrate into a double-sided substrate as in Patent Document 3, complicated processing is required. Moreover, since the insulating layer is a resin, heat dissipation is insufficient, and an inexpensive single-sided substrate cannot be provided with an electrode on the back surface of the light emitting surface, so that the chip cannot be surface-mounted. Implementation becomes complicated.

  In view of the above technical background, an object of the present invention is to provide an LED package that is excellent in heat dissipation and has an LED chip surface-mounted on a substrate.

  That is, this invention has the structure as described in following [1]-[5].

[1] A substrate on which the LED chip is mounted has a plurality of conductive parts made of metal and an insulating part made of an inorganic material and electrically insulating these conductive parts, and the conductive part and the insulating part are chip mounting surfaces. Are integrated in a vertically stacked state from
An LED package, wherein an LED chip is bonded to the conductive portion of the substrate.

  [2] The LED package according to [1], wherein the inorganic material constituting the insulating portion is at least one of aluminum oxide, aluminum nitride, silicon nitride, and zirconium oxide.

  [3] The LED package according to item 1 or 2, wherein the inorganic substance constituting the insulating part has a whiteness degree defined by JIS Z8715 of 50% or more.

  [4] The LED package according to any one of [1] to [3], wherein a metal layer different from the conductive portion is formed on the conductive portion.

  [5] The LED package according to item 4, wherein the metal layer is a plating film formed by electrolytic plating.

  In the LED package according to the invention described in [1] above, the substrate on which the LED chip is mounted has a plurality of conductive parts made of metal and an insulating part made of an inorganic material and electrically insulating these conductive parts. The conductive portion and the insulating portion are integrated in a state where they are stacked in the vertical direction from the chip mounting surface. In such a substrate structure, since the conductive portion penetrates between the chip mounting surface and the opposing surface, when an LED chip is bonded on the conductive portion on the chip mounting surface of the substrate, an electrode is formed on the conductive portion on the opposing surface. Can be connected. Accordingly, the substrate can be used as a double-sided substrate without processing through holes or the like, and the surface mounting of the LED chip is possible.

  Further, the conductive part is a metal and has a thickness of the substrate, so that it functions as a heat sink, and heat generated by the LED chip bonded to the conductive part is directly radiated to the conductive part or via an insulating part. Since heat is radiated to other conductive parts, excellent heat radiation performance can be obtained.

  Further, since the inorganic material constituting the insulating portion has a small coefficient of thermal expansion, broken lines and disconnections are less likely to occur even when the amount of heat generation is large or heat and cooling are repeated.

  In the LED package described in [2] above, since the insulating portion is formed of at least one of aluminum oxide, aluminum nitride, silicon nitride, and zirconium oxide, excellent electrical insulation and heat dissipation are obtained. It is done. In addition, since the thermal expansion coefficient of these inorganic substances approximates the thermal expansion coefficient of the sapphire substrate used in the LED chip, the thermal contraction stress generated in the joint part of the LED chip is small, the joint part breaks, Cutting or peeling does not occur or is difficult to occur.

  Since the LED package described in [3] is formed of an inorganic material having a whiteness of the insulating portion of 50% or more, the light emitted from the LED chip is diffusely reflected and the light use efficiency is good.

  In the LED package according to the above [4], since the metal layer is provided on the conductive portion, the formation of an oxide film on the surface of the conductive portion is suppressed and the solder bonding property with the LED chip and the bonding wire is improved. Excellent conductivity and heat dissipation can be obtained.

  In the semiconductor package described in [5] above, the metal layer on the conductive portion is formed by electrolytic plating. Electrolytic plating can easily form a metal layer and does not require a mask because no metal layer is formed on the insulating portion. In these respects, the electrolytic plating can form a metal layer at low cost.

It is a perspective view of one Embodiment of the board | substrate used for the LED package concerning this invention. It is a perspective view of other embodiment of the board | substrate used for the LED package concerning this invention. It is sectional drawing which shows one Embodiment of the LED package of this invention which mounted the LED chip on the board | substrate of FIG. It is sectional drawing which shows other embodiment of the LED package of this invention which mounted the LED chip on the board | substrate of FIG. It is sectional drawing which shows other embodiment of the LED package of this invention which mounted the LED chip on the board | substrate of FIG. It is sectional drawing of the LED lamp using an LED package. It is sectional drawing which shows the laminated material which is a manufacturing material of a board | substrate. It is sectional drawing which shows the manufacturing method which manufactures the laminated material of FIG. It is sectional drawing which shows the other manufacturing method which manufactures the laminated material of FIG. It is sectional drawing which shows the further another manufacturing method which manufactures the laminated material of FIG. It is a perspective view which shows the raw material which is a manufacturing material of a board | substrate. It is sectional drawing which shows the manufacturing process of the raw material of FIG. It is sectional drawing which shows a part of other manufacturing process of the raw material of FIG.

[LED package]
1 and 2 are perspective views showing substrates (1) and (2) used in the LED package of the present invention, and FIGS. 3A, 3B and 4 show LED packages (3A) and (3B) using these substrates. (4). In these drawings, the upper surfaces of the substrates (1) and (2) are the chip mounting surface (M1), the lower surface is the facing surface (M2) of the chip mounting surface (M1), and the chip mounting surface (M1) and the facing surface (M2). ) Indicates the thickness (t) of the substrates (1) and (2).

  In the substrate (1), each of the conductive portions (11a) (11b) and the insulating portion (12) penetrates between the chip mounting surface (M1) and the opposing surface (M2), and is electrically conductive on the chip mounting surface (M1). The part (11a), the insulating part (12), and the conductive part (11b) are arranged in this order, and these are integrated. Accordingly, the conductive portions (11a) (11b) and the insulating portion (12) are stacked vertically from the chip mounting surface (M1), and all of the conductive portions (11a) (11b) and the insulating portion (12) are mounted on the chip mounting surface. It is exposed on both the (M1) and the opposing surface (M2), and has a thickness (t) of the substrate (1). The dimension of the chip mounting surface (M1) in the stacking direction of the three members is represented by (w), the dimension of the conductive part (11a) in the stacking direction is (w1a), and the dimension of the insulating part (12) is (w2). ), The dimension of the conductive portion (11b) is represented by (w1b). The dimension of the other side of the chip mounting surface (M1) is represented by (d).

  In the present invention, as long as the substrate has a plurality of conductive portions, and these conductive portions are electrically insulated by the insulating portions, the number of each is arbitrary. The substrate (2) shown in FIG. 2 has three conductive portions (11c) (11d) (11e) and two insulating portions (12) stacked alternately. Moreover, the dimension of each part can also be set arbitrarily, for example, the board | substrate (1) of FIG. 1 differs in the dimension of two electroconductive parts (11a) (11b), and the dimension (w1a) of one electroconductive part (11a). ) <Dimension (w1b) of the other conductive portion (11a).

  The conductive portions (11a) (11e) are made of metal. Since the conductive portions (11a)... (11e) are wiring portions and also function as heat sinks, it is preferable to use a metal having good conductivity and heat dissipation, and aluminum and copper can be recommended. Aluminum may be either pure aluminum or an aluminum alloy, and a material having good electrical conductivity and strength and hardness as a substrate is appropriately used. Copper can be used regardless of the type and alloy composition of rolled copper, electrolytic copper, etc., and has a good conductivity and a composition having strength and hardness as a substrate.

  Further, as shown in FIGS. 3A to 4, on the conductive portions (11a)... (11e), in order to improve the conductivity and bonding properties with the LED chip (20) and the bonding wire (15), the conductive portions It is also preferable to provide a metal layer (13) different from (11a) ... (11e). When copper is used as the conductive portion (11a) (11e), surface oxidation is likely to occur, and the oxide film causes a decrease in conductivity. Therefore, the formation of the metal layer (13) causes the conductive portion (11a) ( 11e) surface oxidation can be prevented. In addition, since aluminum is a metal with poor solder adaptability, solder joint characteristics can be improved by forming a metal layer (13) on the conductive portions (11a)... (11e) of aluminum. The metal of the metal layer (13) is preferably gold, silver, or nickel from the viewpoint of preventing surface oxidation of the conductive portions (11a) to (11e) and improving solder joint characteristics. Since these metals have good thermal conductivity, they do not reduce the heat dissipation of the conductive portions (11a) (11e).

  The method of forming the metal layer (13) is not limited, and the method of plating the conductive portions (11a) ... (11e) to form a plating film as a metal layer, the method by vapor deposition, the conductive portions (11a) ... (11e) Examples thereof include a method in which a clad material is used as the material, a core material of the clad material is used as a conductive portion, and a skin material is used as a metal layer. Among these forming methods, electrolytic plating can be recommended. Electroplating makes it easy to form the metal layer (13), and no masking is required because the metal layer (12) is not formed on the insulating portion (12). In these respects, the electroplating can form the metal layer (13) at low cost.

  Of course, the metal layer (13) is not formed on the insulating portion (12). However, since the dimension (w2) of the insulating portion (12) is small as described later, the metal layer (13) In order to surely prevent a short circuit, it is preferable to form an insulating insulating layer (16) having a thickness equal to or greater than the thickness of the metal layer (13) on the insulating portion (12) (see FIG. 3A). The insulating layer (16) can be easily formed by a simple method such as applying an insulating paint after forming the metal layer (13). The type of the insulating paint is not limited, but since the LED chip (20) is mounted, it is preferable to use an insulating paint with little light degradation and high light reflectance.

  In the illustrated example, metal layers (13) are formed on both the chip mounting surface (M1) side and the opposing surface (M2) side of the conductive portions (11a)... (11e). This is because the substrates (1) and (2) used in the present invention are double-sided substrates in which the conductive portions (11a)... (11e) penetrate between both surfaces, and the conductive portions (11a). This is because the electrode is connected to another substrate or the like so as to be energized. Therefore, the metal layer (13) is preferably formed on both surfaces of the conductive portions (11a)... (11e).

  The insulating part (12) is made of an inorganic material. Inorganic substances have better heat conductivity and higher heat dissipation than resins. Ceramics such as aluminum oxide, aluminum nitride, silicon nitride, and zirconium oxide can be recommended as inorganic materials that have both electrical insulation and heat dissipation. As the LED chip (20) to be mounted, a sapphire substrate (aluminum oxide substrate) is generally used, and since the thermal expansion coefficient of the ceramic described above approximates that of the sapphire substrate, the LED chip (20) The heat shrinkage stress generated in the joint is small, and the joint is not broken or cut off or peeled off.

  Moreover, since the LED chip (20) is mounted on the substrates (1) and (2), the surface of the insulating portion (12) acts as a reflector. For this reason, it is preferable to use white or near-white inorganic material that diffusely reflects light. When light is diffusely reflected, the utilization efficiency of light emitted from the LED chip (20) is increased. As for the degree of whiteness, the whiteness specified by JIS Z 8715 is preferably 50% or more, and particularly preferably 70% or more.

  When the substrate has a plurality of conductive parts or a plurality of insulating parts, these materials may be the same material or different materials. In the case where different materials are used for the plurality of conductive portions, the heat radiation efficiency can be increased by producing the conductive portions for joining the LED chips with a material having higher thermal conductivity. Moreover, the light extraction efficiency to the front can be improved by manufacturing the conductive part for joining the LED chip with a material having high light reflectance.

  In the substrates (1) and (2), the dimensions and thickness of the conductive parts (11a) to (11e) and the insulating part (12) are not limited. The dimensions and mounting method of the LED chip (20), and the insulation at the operating voltage It can be arbitrarily set according to the dimensions required for securing, the heat generation amount of the LED chip (20), and the like.

  FIG. 3A shows an example of an LED package (3A) in which an LED chip (20) is surface-mounted on the substrate (1). The two conductive portions (11a) and (11b) have a difference in size in the stacking direction, and the size (w1b) of one conductive portion (11b) is larger than the size (w1a) of the other conductive portion (11a). The LED chip (20) is soldered to the large conductive portion (11b), the bonding layer (14) such as a conductive adhesive is bonded, and the bonding wire (15) is bonded to the small conductive portion (11a). Thereby, the heat generated from the LED chip (20) can be efficiently radiated from the large conductive portion (11b).

  In the present invention, “joining the LED chip to the conductive part” is a state in which the LED chip is connected so that the conductive part becomes a main heat dissipation path, and specifically, between the LED chip and the conductive part. In this state, only materials necessary for bonding such as solder and conductive adhesive are present. The electrical connection by the bonding wire is not included in the state where the LED chip in the present invention is bonded to the conductive portion.

  Further, the dimensions of the insulating part (12) are not limited as long as sufficient electrical insulation can be obtained under the operating voltage. For example, since the voltage when the LED chip is mounted is generally 5 V or less, referring to the substrate (1) in FIG. 1, even if the dimension (w2) of the insulating part (12) is several μm, the conductive part (11a) (11b ) Can be insulated. However, in consideration of safety as an LED device, it is preferable that insulation can be performed even at a voltage of 1 kV or more, and the dimension (w2) of the insulating portion (12) is preferably set to 30 μm or more.

  In the present invention, the thickness (t) of the substrate (1) can be arbitrarily set as long as the strength as the substrate is satisfied. Moreover, since the thickness (t) of the substrate (1) is also the thickness of the conductive portions (11a) and (11b), the conductive portions (11a) and (11b) having such a thickness (t) have high heat transfer capability. It functions as a heat sink.

  Furthermore, as long as the LED chip is bonded so that at least one conductive part is a main heat dissipation path, the method of connecting the LED chip chip to the conductive part is not limited. In the LED package (3A) of FIG. 3A, the LED chip (20) is bonded on one conductive part (11b) via a bonding layer (14), and connected to the other conductive part (11a) with a bonding wire (15). In this example, one of the conductive portions (11b) is the main heat dissipation path. The LED package (3B) in FIG. 3B is an example in which the LED chip (20) is joined with ball-shaped solder (17) so as to straddle the two conductive parts (11a) and (11b). (11a) and (11b) are heat dissipation paths. In the LED package (4) of FIG. 4, the LED chip (20) is bonded to one conductive portion (11d) with a conductive adhesive or solder (14), and the other two conductive portions (11c) ( 11e) is connected with a bonding wire (15), and one conductive portion (11d) is the main heat dissipation path.

[LED lamp using LED package]
FIG. 5 shows an LED lamp (5) produced using the LED package (3) of the present invention.

  In the LED package (3), a resin outer frame (21) is attached to the outer periphery of the substrate (1) of the LED package (3A) of FIG. 3A, and the chip mounting surface (M1) and outer frame (21) of the substrate (1) are attached. ) Is filled with a resin sealing material (22), and a resin lens (23) is integrally formed. The sealing material (22) mitigates the impact on the LED chip (20), prevents the intrusion of moisture, protects the LED chip (20), and improves handling. In addition, a pigment can be mixed with the resin for the sealing material in order to adjust the color tone of the lamp. For the purpose of improving optical performance, a reflector is attached to the inner surface of the outer frame (21) or a reflector-integrated outer frame is used, and a lens (23) is mounted on the upper surface of the sealing material (22). It is also preferable to attach. Moreover, the handling property of the LED package is improved by covering the LED chip (20) with the resin in this way.

  The LED package (3) obtains the above effect by covering the LED chip (20) with a resin outer frame (21) and a sealing material (22). However, the LED package of the present invention is an LED chip. It is not an indispensable requirement to cover the substrate on which the substrate is mounted with various coating materials. A substrate in which an LED chip is mounted on a substrate defined by the present invention is included in the present invention regardless of the presence or absence of a coating material. Moreover, since the heat dissipation is reduced when the substrate on which the LED chip is mounted is covered with a covering material, it is also preferable to form the covering material in a shape that exposes part of the substrate.

  In the LED lamp (5), the conductive portion (11a) (11b) of the substrate (1) of the LED package (3) is soldered to the copper wiring portion (25) formed on the heat conductive insulating substrate (24). Is. In the figure, (26) indicates solder. In addition, since the conductive portion (11a) (11b) is covered with the metal layer (13), the conductive portion (11a) (11b) is connected to the copper wiring via the metal layer (13). Soldered to the part (25).

  In the LED lamp (5), the mounting method of the LED chip (20) on the substrate (1) is the same as that in FIG. 3A. Therefore, the LED chip (20) is interposed on the large conductive portion (11b) via the bonding layer (14). 20) is joined, and the LED chip (20) is connected to the small conductive portion (11a) by a bonding wire (15). Therefore, the heat generated from the LED chip (20) is mainly transferred directly to the conductive part (11b) to which the LED chip (20) is bonded, and is radiated to the heat conductive insulating substrate (24) via the solder (26). Is done. Further, the heat is transmitted from the conductive portion (11a) to the other conductive portion (11b) through the insulating portion (12) and is radiated to the thermally conductive insulating substrate (24). The heat generated from the LED chip (20) is exhausted through the conductive portions (11a) and (11b) as a heat dissipation path, and the conductive portions (11a) and (11b) themselves having the thickness (t) of the substrate (1) Since it acts as a heat sink, heat dissipation efficiency is good. Since the metal layer (13) on the conductive part (11a) (11b) is a metal having good thermal conductivity, the metal layer (13) on the heat dissipation path also functions as a part of the heat sink, thereby improving the heat dissipation efficiency. become.

  Further, since the conductive portions (11a) and (11b) are exposed on both surfaces of the substrate (1), electrodes can be formed on the opposing surface (M2) of the chip mounting surface (M1). Therefore, it can be used as a double-sided substrate as it is without processing for electrode formation such as providing a through hole, and a surface-mount type semiconductor package can be manufactured. Since the conductive portions (11a) and (11b) are also exposed on the side surface of the substrate (1), an electrode can be formed on the side surface.

  In addition, since the inorganic material constituting the insulating portion (12) has a low coefficient of thermal expansion, broken lines and disconnections are less likely to occur even when the amount of heat generation is large or heat and cooling are repeated. In addition, since the linear expansion coefficient of the insulating part (12) approximates the linear expansion coefficient of the LED chip (20), the wire breaks even when soldering to the bottom of the chip like a BGA (Ball Grid Array) board. Hard to do.

[Substrate manufacturing method]
The substrate used in the LED package of the present invention is an integration of the metal constituting the conductive part and the inorganic substance constituting the insulating part, and the means for the integration is not limited, bonding with an adhesive, pressure welding, Examples thereof include brazing and discharge plasma bonding. However, since the organic adhesive is easily deteriorated at high temperatures and is also deteriorated by light, it is preferable to join the metal and the inorganic material directly or via the inorganic material.

  Moreover, a board | substrate can be manufactured also by forming an insulating part in aluminum using the technique of an anodizing process.

  In the following, taking the production of the substrate (1) of FIG. 1 as an example, a method for producing a substrate from a laminate and a method for producing a substrate by anodization will be described in detail.

(1) Method of manufacturing a substrate from a laminated material As shown in FIG. 6, the laminated material (30) is integrated with an insulating plate (32) sandwiched between two metal plates (31a) and (31b). It is a joined three-layer flat plate. When the laminated material (30) is cut along an arbitrary surface along the laminating direction, the cut surfaces of the metal plate (31a), the insulating plate (32), and the metal plate (31b) are respectively stacked in the order of lamination (W1A). ), (W2), and (W1B). Therefore, when the laminated material (30) is cut along a plane along the lamination direction to cut out a rectangular parallelepiped, each of the cut out rectangular parallelepipeds becomes a substrate (1). Then, the metal plates (31a) and (31b) in the laminated material (30), the conductive portions (11a) and (11b), and the insulating portion (12) in the insulating plate (32) substrate (1). In addition, since the metal plates (31a) (31b) and the insulating plate (32) penetrate between the arbitrary cut surface (including the side surface of the laminated material) and the facing surface when the rectangular parallelepiped is cut out, any This cut surface can be the chip mounting surface (M1) of the substrate (1).

  The thicknesses (W1A), (W1B), and (W2) of the metal plates (31a) and (31b) and the insulating plate (32) are the conductive portions (11a) in the three layers of the chip mounting surface (M1) of the substrate (1). ) (11b) and the dimension (w1b) (w1b) (w2) of the insulating part (12), so that the dimension (w1b) (the conductive part (11a) (11b) and the insulating part (12) of the substrate (1) w1b) (w2) can be arbitrarily set by the thickness (W1A) (W1B) (W2) of the metal plates (31a) (31b) and the insulating plate (32) during the production of the laminate (30). The thickness (W) of the material (30) is the dimension (w) in the stacking direction on the chip mounting surface (M1) of the substrate (1). Further, one of the cut dimensions (TA) in the laminate (30) is the thickness (t) of the substrate (1), and the other dimension (DA) is other than the chip mounting surface (M1) of the substrate (1). Therefore, the thickness (t) of the substrate (1) and the dimension (d) of the other side are arbitrarily set according to the cut dimensions (TA) (DA) of the laminated material (30). be able to.

  As described above, a large number of substrates (1) can be efficiently manufactured by manufacturing the laminated material (30) and cutting the laminated material (30).

  The laminate (30) can be manufactured by a well-known laminate integration technique in which a metal plate and an insulating plate are joined or integrated directly or indirectly.

(1-1) Direct bonding As an example of manufacturing a laminated material by direct bonding, as shown in FIG. 7, metal plates (31a) (31b) and an insulating plate (32) are stacked in a required order, and both sides are punched ( There is a method of heating while pressing between 40). This manufacturing process can use a manufacturing process of a copper-clad ceramic substrate called a DBC substrate (Direct Bonding Copper substrate), and generates a eutectic with a ceramic by using a trace amount of oxide contained in Cu (copper ( A laminated material in which a metal plate) and a ceramic substrate (insulating plate) are directly bonded can be manufactured.

(1-2) Indirect joining As an example of manufacturing a laminated material by indirect joining, as shown in FIG. 8, a sheet-like brazing material or active metal between the metal plates (31a) (31b) and the insulating plate (32). There is a method in which the brazing materials (33) and (33) are overlapped with each other, and both sides are sandwiched by punches (40) and heated while being pressurized. For this manufacturing process, a manufacturing process of an aluminum-clad ceramic substrate called a DBA substrate (Direct Brazed Aluminum substrate) or a manufacturing process of a copper-clad ceramic substrate called an AMC substrate (Active Metal Brazed Copper substrate) can be used. The DBA substrate is a substrate obtained by brazing an aluminum plate (metal plate) to a ceramic substrate (insulating plate). The AMC substrate is a substrate obtained by brazing a copper plate (metal plate) to a ceramic substrate (insulating plate) with a brazing material to which an active metal such as Ti or Zr is added. According to these manufacturing methods, it is possible to manufacture a substrate in which the conductive portion and the insulating portion are indirectly joined.

(1-3) Discharge plasma bonding As another method of directly bonding a metal plate and an insulating plate, a discharge plasma bonding method can be given. The discharge plasma bonding method is a known bonding method in which a spark plasma sintering (SPS) sintering mechanism is applied to plate bonding rather than powder sintering. The “discharge plasma bonding method” is also called “SPS bonding method”, “Pulsed Current Hot Pressing (PCHP)”, or the like.

  Specifically, as shown in FIG. 9, metal plates (31a) (31b) and an insulating plate (32) are placed in a graphite die (41) so as to overlap each other, and a graphite punch (42 ), The electrodes (43) and (44) are connected to both the punches (42), and the metal plate (31a) (31b) and the insulating plate (32) are joined by applying pulse current to the laminate. According to this method, a substrate in which the conductive portion and the insulating portion are directly bonded can be manufactured.

  In addition, an insulating plate and metal powder are placed in a die by a discharge plasma sintering method, and the metal powder is sintered by discharge plasma to simultaneously solidify the metal and join the insulating plate to produce a laminated material. It is also possible to do.

  According to said process, many board | substrates can be manufactured efficiently by the cutting | disconnection of a laminated material. In addition, although the laminated material (30) of the example of illustration is three layers, the number of lamination | stacking of a metal plate and an insulating board can be set arbitrarily.

  The manufacturing method of the laminated material is not limited to the above-mentioned method. As another bonding method, diffusion bonding method, molten aluminum is poured onto an insulating plate, the molten aluminum is solidified and the molten metal contact method is bonded to the insulating plate, insulation. A method of forming a metal layer (conductive part) by plating, vapor deposition such as DLC (diamond-like carbon) on a plate, a method of forming a metal layer (conductive part) by printing metal powder on an insulating plate and sintering. It can be illustrated.

(2) Manufacture of substrate by anodizing treatment When the conductive portion is aluminum, the substrate can be manufactured by forming the insulating portion by anodizing the aluminum plate.

  The plate-like material (50) shown in FIG. 10 is an anodized product, and an insulating portion (54) along the longitudinal direction is formed in the middle of the width direction of the aluminum plate, and aluminum is formed by this insulating portion (54). It is divided into two conductive portions (51a) and (51b). The two conductive portions (51a) (51b) and the insulating portion (54) are stacked in a direction penetrating between one surface and the other surface in the plate thickness direction of the material (50). The material (50) cut into the required dimension (DB) is the substrate (1). The conductive portions (51a) (51b) and the insulating portion (54) of the material (10) correspond to the conductive portions (11a) (11b) and the insulating portion (12) of the substrate (1).

  FIG. 11 schematically shows steps (S1 to S4) for producing the material (50) from the aluminum plate (55). Below, the manufacturing method of a raw material (50) is demonstrated, referring FIG.

  (S1) Since the plate thickness (TB) of the aluminum plate (55) is the thickness of the substrate (1), the aluminum plate (55) having the thickness (t) of the intended substrate (1) is used. To do. In this aluminum plate (55), a resist (52) is applied to both surfaces of the portions to be the conductive portions (51a) and (51b). The portion where the resist (52) is not applied exposes aluminum, and the aluminum exposed portion (53) is a portion where the insulating portion (12) is formed. In the illustrated example, there are one exposed aluminum portion (53) on each of the upper and lower surfaces of the aluminum plate (55).

  (S2) The aluminum plate (55) to which the resist (52) is applied is immersed in a treatment solution and anodized. An anodized film (54) is formed on the upper and lower exposed aluminum parts (53), and the film (54) grows in the thickness direction of the aluminum plate (55).

  (S3) The anodized film (54) grown from both sides of the aluminum plate (55) is connected in the middle of the plate thickness direction, and the anodized film (54) penetrates the aluminum plate (55) in the plate thickness direction and the aluminum plate ( 55) is divided in the width direction, and two conductive portions (51a) (51b) and one insulating portion (54) are formed.

  (S4) When the anodized film (54a) grown on the outside of the resist (51) and the aluminum plate (55) is removed by surface polishing or the like, the material (50) shown in FIG. 10 is obtained.

  The material (50) is manufactured by the above process. When the material (10) is cut to the required dimension (DB), the conductive portions (11a) (11b) and the insulating portion (12) penetrate between the chip mounting surface (M1) and the facing surface (M2). The substrate (1) is laminated in the direction. On the chip mounting surface (M1), the dimension (w2) of the insulating part (12) in the three stacking directions corresponds to the dimension of the aluminum exposed part (53). Further, the dimensions (w1a) and (w1b) of the conductive portions (11a) and (11b) are set according to the dimensions of the aluminum plate (55) to be used and the dimensions of the exposed aluminum part (53), or aluminum after anodizing treatment. Set by cutting the board.

  Moreover, since the said insulation part (54) can be formed in the arbitrary places of an aluminum plate (55), if an insulation part (54) is formed in the several places of one aluminum plate (55), it will be 1 time. A plurality of materials (50) in the illustrated example can be manufactured by the anodizing treatment.

  In addition, as shown in FIG. 3A and the like, when the conductive portions (11a) and (11b) are covered with the metal layer (13) by the plating film, the material (50) is plated, and then the required dimensions are obtained. Disconnect. Further, if a clad material obtained by clad a metal layer (skin material) on an aluminum core is used as an aluminum plate to be subjected to anodizing treatment, the metal layer can be formed without adding a process.

  Note that FIG. 11 omits the description of whether or not the resist is applied to the side surface of the aluminum plate (55). However, if the resist is not applied to the side surface, an anodized film is formed. A film is not formed. Whether or not the anodized film is formed on the side surface can be arbitrarily set according to the form of the LED package. For example, in the LED package (3) shown in FIG. 5, a resin outer frame (21) is attached to the outer periphery of the substrate (1), but the conductive portions (11a) (11b) and the outer frame (21) are joined. An anodic oxide film may be formed to improve the properties.

  The method for manufacturing the substrate by the anodizing treatment is not limited to the above steps, and various modifications can be made.

  The aluminum exposed portion (53) can be provided only on one surface of the aluminum plate (55), and the anodized film (54) can be grown to reach the other surface to form an insulating portion. However, the processing time can be shortened by growing the film from both sides as in the above process. Further, since the anodized film (54) grows to a thickness of about 200 μm, it hardly grows further. Therefore, when the thickness (TB) of the aluminum plate (55) exceeds the growth limit of the film, aluminum is exposed on both sides. It is necessary to provide the part (53) and form the anodized film (54) from both sides. The growth limit of the anodized film varies depending on the anodizing conditions, the chemical composition of the aluminum plate, etc., and the above 200 μm is only an example of the growth limit.

  Furthermore, as shown in FIG. 12, it is also preferable to promote the formation of the anodic oxide film (54) by forming a recess (56) in the aluminum exposed portion (53) of the aluminum plate (55). If the plate thickness (TB) of the aluminum plate (55) exceeds twice the growth limit of the anodized film, the aluminum plate (55) cannot be penetrated simply by providing a portion where the resist (52) is not applied. By forming the recess (56), the range of the plate thickness (TB) of the usable aluminum plate (55) can be expanded. Since the plate thickness (TB) of the aluminum plate (55) corresponds to the thickness (t) of the substrate (1), the substrate (1 that can be manufactured by inserting the recess (56) when the material (50) is manufactured. ) Thickness (t) can be expanded. In addition, even in an aluminum plate having a plate thickness (TB) that is not more than twice the growth limit of the anodized film (54), the formation of the recess (56) reduces the processing time and reduces the processing conditions. can get.

  In the production of the material (50) by the above-described anodizing treatment, an anodized film that penetrates the aluminum plate (55) is formed on the aluminum exposed portion (53) where the resist (52) is not applied, and this is formed as an insulating portion (54). It is a thing. Since the resist (52) can be applied to a desired portion on the aluminum plate (55), an insulating portion (54) having a desired shape can be formed on the desired portion of the aluminum plate (55). Therefore, it is possible to manufacture a substrate in which a plurality of conductive portions and insulating portions that insulate them are complicatedly stacked. For example, if a resist is applied in a ring shape, a ring-shaped insulating portion is formed, and a conductive portion can be formed inside and outside the ring-shaped insulating portion. Moreover, the said raw material (50) can be manufactured from one aluminum plate, and the several board | substrate from which a lamination | stacking form differs can also be manufactured from one aluminum plate. The thickness (t) of the substrate (1) is determined by the plate thickness (TB) of the aluminum plate (55) used when the material (50) is manufactured, but the dimensions (w1a, w1b) can be arbitrarily set at the cutting position of the material (50) after the material is manufactured.

  On the other hand, the substrate manufactured from the laminated material (30) in FIG. 6 has dimensions (w1a, w1b, w2) in the stacking direction of the conductive portions (11a) (11b) and the insulating portion (12) on the chip mounting surface (M1). Is determined by the plate thickness (W1A, W1B, W2) of the material plates (31a), (31b), (32) of the laminated material (30), so that the conductive portions (11a), (11b) and the insulation are manufactured after the laminated material (30) is manufactured. The dimensions (w1a, w1b, w2) of the part (12) cannot be changed. However, the thickness (t) of the substrate (1) and the dimension (d) of the other side of the chip mounting surface (M1) can be arbitrarily set according to the cutting position of the laminated material (30) after the laminated material is manufactured. .

  Since the conductive portion of the substrate functions as a heat sink and is excellent in heat dissipation, the present invention can be suitably used as an LED package on which an LED with a large amount of heat generation is mounted.

1, 2 ... PCB
3, 3A, 3B, 4 ... LED package
11a, 11b, 11c, 11d, 11e ... conductive part
12… Insulation part
13 ... Metal layer
14… Adhesive layer
15 ... Bonding wire
16… Insulating layer
17 ... Ball solder
20 ... LED chip
21 ... Outer frame
22 ... Sealant
23 ... Lens
30 ... Laminate
31a, 31b ... metal plate
32… Insulating plate
50 ... Material
55 ... Aluminum plate
51a, 51b ... Aluminum (conductive part)
52 ... Resist
53… Aluminum exposed part
54… Anodized film (insulating part)
M1 ... chip mounting surface M2 ... opposite surface

Claims (5)

The substrate on which the LED chip is mounted has a plurality of conductive parts made of metal and an insulating part made of an inorganic material to electrically insulate these conductive parts, and the conductive part and the insulating part are perpendicular to the chip mounting surface. It is integrated in a stacked state,
An LED package, wherein an LED chip is bonded to the conductive portion of the substrate.   The LED package according to claim 1, wherein the inorganic substance constituting the insulating portion is at least one of aluminum oxide, aluminum nitride, silicon nitride, and zirconium oxide.   3. The LED package according to claim 1, wherein the inorganic substance constituting the insulating portion has a whiteness defined by JIS Z8715 of 50% or more.   The LED package according to claim 1, wherein a metal layer different from the conductive portion is formed on the conductive portion. The LED package according to claim 4, wherein the metal layer is a plating film formed by electrolytic plating.

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